1. Field of the Invention
The present invention generally relates to the field of integrated circuits, and more particularly to the production of an initial single-crystal substrate, for example made of silicon, having a discontinuity in the single-crystal lattice, such as a buried trench, for the epitaxial growth of a homogeneous single-crystal silicon layer.
2. Description of Related Art
The processes for fabricating semiconductor components may destroy the crystal continuity of the surface oaf portion of the initial single-crystal semiconductor substrate. This is especially the case during the formation of trenches. The trenches are subsequently filled so as to produce a dielectric insulation, a capacitor or a junction. The semiconductor substrate has, at the position of the trench, a different material without any crystal structure. Consequently, the surface of that portion of the substrate which is occupied by the trench, or more generally by any other local crystal defect, cannot be used to form semiconductor devices, particularly junctions or thin thermal oxides.
This is because the junctions through which a crystal defect passes have leakage currents. The oxides that have grown from a crystal defect exhibit low breakdown voltages or short circuits.
Accordingly, a need exists to overcome these problems and to produce a substrate with a single crystal lattice allowing the subsequent formation of an epitaxial layer of silicon free of crystal defects.